Description

The communications revolution continues to overwhelm users with wave after wave of innovation. Understanding these constantly evolving technologies is crucial for the knowledge workers-part business people, part computer scientists, and part engineers-who develop and implement communications strategies for businesses and governments around the world.

Building on the groundwork of the first edition, Telecommunications Primer, Second Edition, has been fully updated and expanded by more than 40 percent to encompass all the latest advances in the field. Special sections have been added to cover:

Growth of Internet, intranet, and extranet applications.

Scalability and network management in distributed systems.

Advances in digital and cellular systems in North America, Europe, and Asia.

Asynchronous Transfer Mode and developments in switching and routing protocols.

The 1996 Telecommunications Act.

Like the first edition, Telecommunications Primer, Second Edition is organized in three parts:

Signals: The forms in which messages are exchanged.

Building blocks: The devices and procedures that generate, transport, and receive signals, and

Networks: The systems that transfer information between people, between machines, and between people and machines.

Telecommunications Primer, Second Edition presents a wealth of information in terms that make it accessible to readers from many different disciplines. Numerous illustrations, cross-references, and a complete glossary and reading guide make it an indispensable reference book for the knowledge workers of the 21st Century.

Preface

This, the second edition of Telecommunications Primer, has the same objective as the firstÑto be a sourcebook on telecommunication facilities and protocols for knowledge workers. Published in 1995, the first edition is fast becoming out-of-date in many areas. In the past three or four years, major advances have been made in technology, concepts, and operations. Among them are:

Growth of Internet: from a network connecting some 50,000 networks containing 3 million hosts in 1994, Internet has grown rapidly. In 1998, it was estimated to connect some 2 million networks containing 40 million hosts. The growth of Internet has stimulated governments to plan national and global information infrastructures (NIIs and GIIs). Also, commercial users have invented intranets and extranets to share private information among employees, customers, and suppliers.

Scalability and Network Management: the rapid growth of data traffic has caused all network providers to review their options for converting operations from a centralized format that is growth-limited, to a decentralized format that can grow indefinitely. As part of this strategy, they are establishing distributed management systems with automated agents.

Deployment of Digital Cellular Radio Systems: North American time-division and code division multiple access systems (TDMA and CDMA) have been deployed that are compatible with earlier FM-AMPS. In Europe, Global System for Mobile Communications (GSM) has been expanded and updated. In Europe, Japan, and the United States, personal communication systems are being deployed in the 1.9-GHz personal communication services (PCS) band.

Optical Fiber Cables Encircle the Globe: individual undersea cable systems that span the Atlantic, Indian, and Pacific basins have been interconnected. In addition, undersea cable systems are being deployed around Africa and South America. They all employ wavelength-division multiplexing. As a related matter, most fiber-optic network operators experienced fiber exhaust in 1977 and have adopted wave length division multiplexers (WDM) to increase capacity without laying new fibers.

Asynchronous Transfer Mode: as the need for high-speed switching has become real, ATM has overcome early problems associated with flow control (and other operations) and is the heir apparent to the next generation switching machine.

Digital Video: MPEG standards have created bandwidth efficient digital video and television signals. It has been deployed in direct broadcasting satellites and in terrestrial, high-definition television service.

1996 Telecommunications Act: among other things, the Act opens local service to competition, allows local exchange companies to enter the long-distance market, permits cable companies to offer telephone services, and permits telephone companies to offer television services.

Without doubt, on the eve of the second millennium, the first edition does not describe all of the technology of importance to the practicing knowledge engineer. To cover the new environment, new material has been added, existing material has been updated to reflect the developments of the last three to four years, and the text has been reorganized. Principally, the changes and additions are:

Introduction

Expansion of this section to two chapters to bring the soft topics together in one place.

Addition of new chapter on transfer modes to emphasize the interdependence of switching/routing and multiplexing, including expanded discussion of relation among X.25, frame relay, SMDS, and ATM networks

Inclusion of traffic engineering in discussion of local and long-distance networks

Discussion of the use of ATM for high-speed networks, television distribution, and local-area networks (LANs)

New chapter on LANs, MANs, and Internet; includes description of the operation of routers and gateways, intranets and extranets, and new initiatives such as Internet2 and vBNS

Addition of discussion of national and global information infrastructure initiatives

Inclusion of SNA in enterprise network discussion, including subarea and APPN operation

Discussion of network management systems including SNMP, and management of non-OSI devices.

The result is a 40% larger book, with over 100 new diagrams. In addition, I have included review questions. Because my intent is to remind you of the information contained in each Section, they follow the sequence of the text and should present no difficulty for the reader.

For an author, the publication of a new edition is exciting. In my case it is tempered by the realization that it will all have to be done again in three or four years as the tempo of change continues to increase. I do hope you find the second edition of Telecommunications Primer a worthy addition to your technical library.